Use N/A instead of NaN by default? about d3-format HOT 3 CLOSED

D3 4.12.2:

d3.format('.2')(undefined) // "NaN"
d3.format('.2')(null) // "0"
d3.format('.2')(NaN) // "NaN"

These are the string representations of what Number() returns when given the above test values.

I don't think any chosen output would suit everyone in this case, so it would be best handled by wrapping the formatter.

NaN at least draws attention to missing data so you can do something about it - whether that be formatting expected missing data to empty string, or fixing a bug that results in unexpectedly missing data. Perhaps a change could be made to draw attention to the null case in the same way.

from d3-format.

Yes, the locale should be able to specify what to display for NaN input. For example in U.S. English I’d probably use "N/A" instead of "NaN". Likewise we might want to short-circuit some of the formatting logic. For example this:

d3.format('+%')(NaN)

Should probably return "N/A" (or "NaN"), not "+NaN%" as it currently does. But if the format has padding or alignment, that should probably be observed even while the value itself is formatted as "N/A".

from d3-format.

You can now localize NaN, but I’d like to switch to using N/A by default instead of NaN for the next major release, so repurposing this issue.

from d3-format.